Aaaaaaannnnnnnd I'm STILL having problems with this booking. I'd previously contacted the VA rep on this forum and he got the Operations Team to look at it, they had to "push" the flights over to Delta's systems and after two attempts, it was all finally fixed (or so I thought) and everything was displaying correctly on the Delta site, as per my grateful post here on 26th July, acknowledging the team's assistance. Well, 3 days later, it went wrong again - I received yet another copy of my itinerary from VA, no idea why as I hadn't requested it and there had been no other changes to any of the flights that I could see (I'd already received an updated itinerary when the LAX-SEA flight was changed, which seemed to be the start of these issues). I checked the Delta website and sure enough, VA2 had vanished AGAIN so somehow any "activity" on VA's systems with regards to this booking (in this case, the resending of the itinerary) has somehow stuffed up what's being sent across to Delta's systems.
Hugely frustrating and worrying as well - Delta have told me that they cannot see VA2 at all on the booking, only my flights SEA-LAX and SYD-PER. I don't know if their reservations system and the check-in system at the airport show the same information, but if so, when I check in for the start of my return trip in SEA, Delta won't be able to check me in for the onwards flight on VA2 if it's not there!!! I sent another PM to the rep nearly 2 weeks ago, but haven't had a response so far, so not sure if they're trying to find a solution or if they've given up on the problem!